1. Field of the Invention
This invention relates to sheet feeding apparatus which clamps a sheet of material and then feeds it to a working machine such as a press or punching machine, and more particularly a sheet feeding apparatus provided with means for correcting the position of the sheet when it is clamped.
2. Description of the Prior Art
When clamping a sheet of material mounted on a table and then transferring the clamped sheet to a press, for example, it is necessary to precisely set the sheet at a predetermined position on the table at the time of clamping the sheet with a suitable clamping device. Because, at the time of clamping, if the sheet were not set at a correct position, the relative positional relation between the sheet and the clamping device would become erroneous so that press work could not be made at the correct position of the sheet when the sheet is conveyed to the press to be pressed.
According to the prior art method, each time the sheet is mounted on the table, the positional error of the sheet has been manually corrected so that the amount of the correction is not always equal and the surface of the sheet is contaiminated by an operator's hand.